Pattern formation employing self-assembled material

Abstract

In one embodiment, Hexagonal tiles encompassing a large are divided into three groups, each containing ⅓ of all hexagonal tiles that are disjoined among one another. Openings for the hexagonal tiles in each group are formed in a template layer, and a set of self-assembling block copolymers is applied and patterned within each opening. This process is repeated three times to encompass all three groups, resulting in a self-aligned pattern extending over a wide area. In another embodiment, the large area is divided into rectangular tiles of two non-overlapping and complementary groups. Each rectangular area has a width less than the range of order of self-assembling block copolymers. Self-assembled self-aligned line and space structures are formed in each group in a sequential manner so that a line and space pattern is formed over a large area extending beyond the range of order.

What is claimed is: 
     
       1. A structure comprising a substrate having a pattern of protrusion or recess from a horizontal surface, wherein said pattern comprises a hexagonal array of instances of a unit pattern having a shape of a regular hexagon, wherein said instances of said unit patterns are repeated within said hexagonal array such that sides of regular hexagons from each neighboring instances of said unit pattern are coincident, wherein said hexagonal array has a minimum periodicity of a lithographic dimension, wherein each instance of said unit pattern comprises a plurality of circles of a same diameter and having a hexagonal periodicity within said instance, wherein a collection of circles of said same diameter from two neighboring instances of said unit pattern does not have a hexagonal periodicity. 
     
     
       2. The structure of  claim 1 , wherein said same diameter is sublithographic. 
     
     
       3. The structure of  claim 1 , wherein said pattern is a pattern of protrusion. 
     
     
       4. The structure of  claim 3 , wherein said pattern of protrusion is defined by a plurality of cylinders having said same diameter. 
     
     
       5. The structure of  claim 4 , wherein said plurality of cylinders comprises a polymeric component of a non-photosensitive polymeric resist. 
     
     
       6. The structure of  claim 5 , wherein said plurality of cylinders is located directly on each of said pattern of protrusion. 
     
     
       7. The structure of  claim 6 , wherein edges of said plurality of circles coincide with cylindrical surfaces of said plurality of said cylinders. 
     
     
       8. The structure of  claim 3 , wherein said pattern of protrusion is defined by circular polymeric cylinders located on and above said horizontal surface. 
     
     
       9. The structure of  claim 8 , wherein said minimum periodicity of said hexagonal array is not the same as a minimum distance between an adjacent pair of axes of said circular polymeric cylinders. 
     
     
       10. The structure of  claim 3 , wherein said horizontal surface is a substantially planar surface of said substrate that contiguously extends above an entirety of said substrate. 
     
     
       11. The structure of  claim 3 , wherein said horizontal surface is an interface between said substrate and structures defining said pattern of protrusion. 
     
     
       12. The structure of  claim 11 , further comprising a contiguous recessed region having a bottom surface that is recessed below said horizontal surface and having sidewalls that underlie peripheries of said structures defining said pattern of protrusion. 
     
     
       13. The structure of  claim 1 , wherein said pattern is a pattern of recess. 
     
     
       14. The structure of  claim 13 , further comprising a matrix of a polymeric component of a non-photosensitive polymeric resist in which said pattern of recess is present. 
     
     
       15. The structure of  claim 14 , wherein said matrix contains cylindrical openings that define said pattern of recess. 
     
     
       16. The structure of  claim 15 , wherein edges of said plurality of circles coincide with cylindrical surfaces of said cylindrical openings. 
     
     
       17. The structure of  claim 13 , wherein said pattern of recess is defined by cylindrical trenches extending downward from said horizontal surface. 
     
     
       18. The structure of  claim 17 , wherein said minimum periodicity of said hexagonal array is not the same as a minimum distance between an adjacent pair of axes of said cylindrical trenches. 
     
     
       19. The structure of  claim 1 , wherein said plurality of circles of said same diameter within each instance of said unit pattern are arranged in a hexagonal arrangement. 
     
     
       20. The structure of  claim 19 , wherein said unit pattern includes, and does not include more than, seven circles of said same diameter.